Problem: What do the following two equations represent? $3x-4y = -3$ $16x+12y = -1$
Explanation: Putting the first equation in $y = mx + b$ form gives: $3x-4y = -3$ $-4y = -3x-3$ $y = \dfrac{3}{4}x + \dfrac{3}{4}$ Putting the second equation in $y = mx + b$ form gives: $16x+12y = -1$ $12y = -16x-1$ $y = -\dfrac{4}{3}x - \dfrac{1}{12}$ The slopes are negative inverses of each other, so the lines are perpendicular.